Ear protector valve



Jan- 11' 1949 J. VOLKMANN 2,458,884

EAR PROTECTOR VALVE Filed Jan. 3,' 1946 Patented Jan. 11, 1949 UNITED. STATE PATENT oFFlcE EAR rno'rli'ron vALvE Application January- 3, 1946, Serial No. 638,881

(Cl. 12S-152) y i 5 claims.

:This invention relates to acoustic devices and more particularly to an earplug member which includes, valve means for opening and 'closing av communication channel through the earplug.l

In connection with the use ofy acoustic devices of the character referred to, it may be desirable to hear a relatively weak acoustic signal and im mediately thereafter to protect the ear against intermittent loud noises. An example is the situ-4 ation of an infantryman ring a recoil-less weapon which is characterized by an exceedingly heavy discharge. The infantryman is required to hear a relatively low-'voiced'oralncommand and then to iire his weapon. Various other situations suggest themselves where the use of selectivity and flexibility in the operation of acoustic devices become highly important. The use of a telephone in noisy oflices and factories may be greatly facilitated by some acoustic protection. l An object of the invention is to improve acousticdevices and to devise an earplug member which includes valve means for opening and 'closing a communication channel through the earplugl member while the latterl is inserted in an ear. Another object of the invention is to, ,provide a simple, novel and efficient earplug member including valve means which may be operated either directly by hand or indirectly in connection with the use of other communication equipment. Other objects will appear from the following description.

In the accompanying drawings:

Figure l is a sectional view illustrating a preferred form of earplug member of the invention; and

Figure 2 is a cross section and partial elevation taken on the line 2-2 of Fig. 1.

The earplug of the invention in a preferred form is constructed from two separate units: an insert tip adapted to engage firmly within the auditory canal, and an external valve body secured to the insert tip. Itis conveni-ent to mould these two pieces separately since they are irregular in shape. The material used is highly elastic, manually deformable rubber or the like.

Referring more in detail to the drawings, I0 indicates the insert tip which is a generally L- shaped body of tubular construction, having a communication channel I2 extending all the way therethrough, as shown in Fig. l. Its extremity is formed with a more yieldable sealing iiange I4, hood-like and generally mushroom shaped, returning from the extremity of the tip, having thin edge portions so designed that a minimum of pressure is exerted on sensitive cartilage por'- tions of the ear passage in which the tip may be inserted. The tubular portion curves as shown in Fig. l to conform as nearly as possible to the contour of the average ear canal.

Secured to the tip IU is the acoustic valve body I5 of the invention which may for example consist-,of an enlarged frusto-conical moulded rubber bodyvforrned at its smaller end with a coaxial tubular nipple I6 of a size to 1it snugly within the outer end of the tip |0. If desired, these two tubular members may be solidly secured together by cementing with a rubber cement or other adhesive. Preferably the valve body is formed with a shoulder at the base of the nipple I8 against which the tip abuts snugly, establishing a standard length for the tip l0.

The valve body is further formed with an axial communication channel 20 extending part way through as shown in Fig. l, stopping in the larger part of the body l5. At one side the valve body has been partly cut through along a plane normal to the body axis, the cut forming a closed slit which passes through roughly one-half of the body I5 in a plane normal to the axis of the ybody and intersecting the communication channel 20 near its closed outer end. Adjacent to the outer side of the cut there is an integral thick diagonal arm 24 which extends longitudinally outward from the large end of, and divergent from the axis of, the body I5. When the tab 24 is forced into a position such as the dotted line position indicated in Fig. l, the opposed and normally closed portions of the valve body at the sides of the cut are caused to move apart, thus forming an appreciable opening which communicates with the channel 20, as may be observed from the dotted line showing. Upon releasing the tab, the cut portions spring together in substantially sealed relation, thus closing the channel.

The arm 24 is preferably arranged on the Valve body in a position such that it is adapted to extend out from the wearers head in an offset manner and may be readily beni-l inwardly by pressing with the i'lnger. It may also be desired to operate the valve by pressing a telephone hand-set unit against the ear. This is entirely feasible with the arrangement described since the olTset position of the tab lends itself very well to being pressed inwardly by the case of the telephone hand-set receiver.

The particular structure described may be varied in several respects. The entire plug member may be made up of a single piece of material rather than being formed in two pieces and cemented together. However, the two-piece type of construction has some advantages as the tip member has utility in various other connections. Similarly, the valve body may be provided with other means of opening and closing the passage through Athefearplug ,f-For example, I may iemploy spring-,operatedrvalves of .various .tylesouilt into the valve body in some convenient manner. Various other types of earplug members, either with or without a sealing flange may alsabefcombined with th-e valve means of the invention,

An insert tip of the characterrdescribed,when closed, gives an average acoustic .insillation vfof more than 2O decibels. Theyalve bndyvna Sealed position provides a substantial-closure andhence jr it also provides a similarly high degree cfacus'tic insulation. However, only a zvenwslightpening of the valve permits passage of sound.

The device may be easily and cheaplymanufactured and is simple to use and keep in working condition. It offers a #quick and =positive means of selectively :insulating fagainst knoise while permitting speechcommunication wnenadesired.

I'claim:

1. An acoustic valve foran `earplugcomprist ing a slitted velastic 'manually deformable I'body portion connected `to `the -plug, saidfbodyf-having a blind sound-communication passage therein intersecting the slit and `-open'through one end of the body, and -means for A'moving the portions beside the slit apart "from one'andth'er.

2. An acoustic `device comprising-'anfinsert'ftip 'foi-'use in an earcanal, said tip "having =a comrnunication channel therethrough, `a valve ".bo'dy of elastic manually deformable `material Lhaving a blind -opening connecting lwith hthe :com-

munication channel, a slit dbeing kformed 'partly across the Ybody and passage 'normally'losedvin the unstressed 'form pf 'the fdevice, and means for resilientlyopeningthe'slit atl wil 3. An-ear guard and'valvecomprisinga `frustoconical l'body of highly Jelastic I`manually {deformcluding an ear-tting tubular tip forming an open continuation of said passage, said body being slitted across the said passage, said slit being normally closed in the unstressed condition of the article, and a stiff arm united with the bodyaatthe outerside ofitherslitamanually operable to open the slit fat 'will 'fior .faimission of sound.

4. The structure of claim 3 wherein said arm isxtended longitudinally outward and divergent yfrom/the axis of the device, whereby an object rpnessedrtoward therhead over the ear will open i'thefsllt.

'.aninrproved article of manufacture, an earjguaniand .valve comprising a body of elas- 'ticmanually deformable rubber-like material inolnding I,a :tubular tip portion insertable in the auditory canal and an enlarged head portion at the puter end of the tip having a blind passage therein open to the extremity of Afthe tip, said head forming aa closed outer Tend ilfor ithe "tubular tip Cand constituting 'La stop to prevent iinsexftion Aof ithetip' beypntlfa rpredetemiined fliistance'inthe eanssalid headbeingrslit-,zacross fromoneesidessub- -lstantially Inormally @to fthe amis .of @the botiy and xso #that `-the slit n#remains yclosed in ithe'sunstfessed condition.dfthe'article, andaniintegral; thickened valveeoperating :arm mn fthe said lenlarged ibndy portion forming ra f continuation -iof 'the material 'besidean artstherouterl-sidemfeaidrsiit.

UJGHN.

imarmmvcns mm1) ','The following references are of :recordlin tithe UNITED -rST-A'ITES SBAMNiIS Certificate of Correction Patent No. 2,458,884. January 11, 1949.

JOHN VOLKMANN Itis hereby certified that error appears in the above numbered patent requiring correction as follows:

The name of the assignee Was erroneously described and specified as "United States of America as represented by the Execut've Secretary of the Olice of Scientic Research and Development, and The President and Fellows of Harvard College Whereas said name should have been described and specified as Umted States of America as represented by the Executive Secretary ofthe Ojjce of Scientific Research and Development, as shown by the record of assignments in this oce;

and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oce.

Signed and sealed this 10th day of May, A. D. 1949.

[IML] THOMAS F. MURPHY,

Assistant Uomnnz'aaz'oner of Patents. 

